When you say rebooting did you simply turn your iPad off and then turn it on again? If this was what you did try doing a reset. To do this hold the home and power buttons till the iPad turns off. Then turn your iPad back on like normal and it may have rectified the problem (it normally works). If this doesn't work it may be that your volume key is constantly being activated by a hardware fault. Have you checked that the key isn't stuck in and therefore activating the switch. Also check you don't have a case on it that might be pushing the volume key down.
The IPad Forum is a community of members from all walks of life and from all over the world coming together to share our experiences and to help each other learn about this wonderful piece of technology the Ipad. There is a wealth of information already here in the many threads we have so doing some searches will answer most of the questions you have. If then you cannot find the answer you are seeking then by all means post your question. There are many friendly and informed members here only too willing to help you.